Maybe not for a home user, but being able to crash a server while logged on as a regular joe user would be a huge deal for any admin serious about security. If permanent damage is possible like the original poster suspects could be done, things could get even nastier.

That said, since micro-code updates have been around for ages (in computer-time) without being abused, it's hard to imagine this would suddenly become a problem for AMD. Interesting read though, compliments to the original poster.